title: Do drug interaction alerts between a chemotherapy order-entry system and an electronic medical record affect clinician behavior?
abstract: BACKGROUND
  We developed an enhancement to a chemotherapy order-entry system that alerted prescribers to potential drug interactions between patients' usual outpatient medications and those prescribed for onsite cancer treatment. This report summarizes the interactions and analyzes the impact of alerts on clinician behavior.
  
  
  METHODS
  We studied electronic orders created from November 2010 to December 2011 by oncology clinicians at two comprehensive cancer centers who shared a chemotherapy order-entry system and an ambulatory electronic medical record. The enhancement generated an alert if a new chemotherapy system order for an antineoplastic agent or supportive care medication interacted with an existing medication in the ambulatory record, and tracked prescribers' responses.
  
  
  RESULTS
  New chemotherapy system orders triggered 29,592 drug interaction alerts. New orders for antineoplastic agents accounted for 495 (32.6%) of 1518 high- and medium-severity alerts. Interactions with antibiotics accounted for the majority of these alerts. New chemotherapy system orders for antiemetics triggered 352 (23.2%) alerts and more than two-thirds were attributed to interactions with analgesic opioids. High- and medium-severity alerts changed prescriber behavior in 224 (14.8%) occurrences, including potentially fatal interactions between meperidine and monoamine oxidase inhibitors. Clinicians who overrode alerts indicated that they would monitor the patient (54.6%), the patient already tolerated the combination (24.5%), and they would adjust the dose (15.1%).
  
  
  CONCLUSIONS
  Cancer patients are at risk of serious interactions between medications ordered for cancer care and those provided for general medical care. Organizations and order-entry applications should develop countermeasures to identify and prevent potentially serious drug interactions.
authors.affiliation: Center for Patient Safety, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA.
authors.forename: Saul N
authors.initials: SN
authors.lastname: Weingart
authors.forename: Junya
authors.initials: J
authors.lastname: Zhu
authors.forename: Joanne
authors.initials: J
authors.lastname: Young-Hong
authors.forename: Holly Barr
authors.initials: HB
authors.lastname: Vermilya
authors.forename: Michael
authors.initials: M
authors.lastname: Hassett
mesh_terms: D000970:Antineoplastic Agents / Q000009:adverse effects*; D004347:Drug Interactions; D057286:Electronic Health Records; D006801:Humans; D050316:Medical Order Entry Systems; D010820:Physicians; D010818:Practice Patterns, Physicians'
chemical_list: D000970:Antineoplastic Agents
keywords: Oral antineoplastic therapy; alerts and reminders; electronic medical record; medication safety